The U.K.’s overseer of data privacy, the Information Commissioner’s Office (ICO) announced today that it has ordered Google to destroy user data it collected during its Street View mapping project, or the regulator will bring criminal proceedings.

Last year, it came to light that Google had collected user data over wireless networks as its Street View cars drove around taking pictures. The data included passwords, email addresses and URLs. Google told the ICO that it had mistakenly held onto four discs of data from U.K. users, and later found a fifth disc. According to the ICO, Google had quarantined the discs and not accessed them, but that was not enough.

The ICO gave Google an enforcement notice to destroy the data. Failure to do so will be considered contempt of court, the Wall Street Journal reports. However, a Google spokesperson told the WSJ that it "cooperated fully with the ICO throughout its investigation, and having received its order this morning we are proceeding with our plan to delete the data."